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Publications (3)1.96 Total impact

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    Article: Soft X-ray Magnetic Circular Dichroism of c(2x2) CuMn Ordered Surface Alloy
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    ABSTRACT: Mn 2p soft X-ray absorption (XAS) spectroscopy excited with circularly polarized synchrotron radiation has been applied to a new class of material, c(2x2)CuMn/Cu(001) two-dimensional ordered surface alloy. A significant X-ray magnetic circular dichroism (XMCD) signal has been clearly observed at T=25K, indicating the existence of the ferromagnetic state under the external magnetic field of 1.4 Tesla. The lineshape analyses of the XAS and XMCD spectra clearly show that the Mn 3d state is rather localized and has a high spin magnetic moment due to its half-filled character. Comment: REVTeX, 3pages, 3figures. To appear in Jpn. J. Appl. Phys. Vol.42 (2003)
    01/2003;
  • Article: Temperature dependence of spin and orbital magnetic moments of Sm 4f electrons in (Sm, Gd)Al2
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    ABSTRACT: X-ray magnetic circular dichroism studies were carried out on (Sm, Gd)Al2, a ferromagnet without net magnetization at a certain compensation temperature. For Sm 4f electrons, the following understandings were obtained: the magnitude of expectation value of orbital magnetic moment () is always larger than that of spin one (), so the cancellation of total spin and orbital magnetic moments cannot be achieved only by Sm 4f electrons and the contributions from Gd ions and conduction electrons are important; when the temperature decreases, the magnitude of both and increases and the gross magnetic moment due to the Sm 4f electrons monotonically deviates from zero. These results tell us that the temperature dependence of magnetic moments related with the electrons other than Sm 4f ones may play important roles in the subtle adjustment of the total spin and orbital magnetic moments to the zero magnetization at the compensation temperature.
    Journal of Electron Spectroscopy and Related Phenomena · 1.96 Impact Factor
  • Article: Direct evidence of ferromagnetism without net magnetization observed by x-ray magnetic circular dichroism
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    ABSTRACT: We have performed x-ray magnetic circular dichroism experiments to study the cancellation of spin and orbital magnetic moments in (Sm,Gd)Al2, a ferromagnet without net magnetization at a certain compensation temperature, Tcomp. We verified the existence of long-range order for both spin and orbital magnetic moments at Tcomp. The spin and orbital magnetic moments of the Sm ion are found always antiparallel coupled and the magnitude of its orbital magnetic moment is always larger than that of spin one, so the cancellation of magnetic moments cannot be achieved by only Sm 4f electrons. We show that the addition of spin magnetic moments of Gd ions and conduction electrons, which are ferromagnetically coupled with the spin magnetic moment of Sm ions, cancels out the surplus orbital magnetic moments in Sm ions completely and results in the zero magnetization at Tcomp. All our experimental results can be reproduced well by atomic multiplet calculations.
    Phys. Rev. B. 70(13).